CORE: Antibody-based Proteomics Shared Resource (Omics Group) PROJECT SUMMARY The ability to simultaneously identify, quantitate, and analyze a large mixture of proteins between different functional states of cells and tissues is the ultimate goal of proteomics, and has the potential to identify signaling pathways important in cancer biology. Because of the diverse nature of proteins and their wide dynamic range of expression, quantitative and sensitive methods are needed in proteomics. Since there is no single technology platform to analyze the whole proteome, multiple proteomic approaches have been developed dependent upon the application. High speed, high sensitivity mass spectrometry profiling is a mainstay for unbiased protein biomarker discovery. Antibody-based proteomic platforms are an important complement to MS that can be used in either targeted discovery or validation modes for both basic research experimental models and clinical studies with patient materials. Antibody-based proteomics have certain advantages in terms of high throughput enabling cost effective analysis of large numbers of experimental or clinical samples, analysis of functional states through use of phosphospecific antibodies (and other PTMs), use of small sample sizes, quantification and the ability to detect low abundance regulatory proteins. The goal of the Antibody-based Proteomics Shared Resource is to provide investigators with cost effective state-of-the-art instrumentation and specialized expertise for analysis of proteomes with antibody-based platforms. Specifically, we will provide services with multiplex Luminex bead-based assays that achieve quantitative picogram level of sensitivity for multiple pathways and analytes, and reverse phase protein arrays (RPPA) platforms for high throughput analysis of large sample sets for both total and activated states of multiple proteins (up to 240) representative of major protein signaling pathways involved in cancer biology. We also provide services and expertise to express components of proteomes as recombinant proteins in the baculovirus system for purification and further characterization, and to generate monoclonal antibodies (MAbs) to specific proteins and post-translational modifications. MAbs are of added value for development of clinical immunoassays for validation studies of candidate protein markers of cancer progression and response to therapies. As the postgenomic era paves the way for proteomics, functional analysis, protein biomarker discovery, or purely understanding the inner workings of protein signaling pathways, are all at the forefront of cancer research.